package pld.car.utils;

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.text.DateFormat;
import java.util.Date;
import java.util.Locale;

public class Public {
	
	public static byte[] getByte(File file) throws Exception {
		byte[] bytes = null;
		if (file != null) {
			InputStream is = new FileInputStream(file);
			int length = (int) file.length();
			if (length > Integer.MAX_VALUE) // 当文件的长度超过了int的最大值
			{
				System.out.println("this file is max ");
				return null;
			}
			bytes = new byte[length];
			int offset = 0;
			int numRead = 0;
			while (offset < bytes.length && (numRead = is.read(bytes, offset, bytes.length - offset)) >= 0) {
				offset += numRead;
			}
			// 如果得到的字节长度和file实际的长度不一致就可能出错了
			if (offset < bytes.length) {
				System.out.println("file length is error");
				return null;
			}
			is.close();
		}
		return bytes;
	}

	// 生成一个标准格式的当前时间
	public static String createDateTime() {
		Date date = new Date(System.currentTimeMillis());
		DateFormat df = DateFormat.getDateTimeInstance(DateFormat.MEDIUM, DateFormat.MEDIUM, Locale.CHINA);
		String dt = df.format(date);
		return dt;
	}
}
